Actually . . .

I misspoke. There is a scene where Billy Jack walks in on a 13-year-old girl having sex with one of the (older) townsmen. Billy Jack asks her her age, she tells him, and then he tells her to get out. She runs out the door and you get a good view of her breasts and behind. Then there's a gunfight between BJ and the dude. The thing is, while BJ may be a little judgmental of the guy for screwing the girl, it is pretty clear that the girl is there willingly.